Pearls are one of the few gemstones that come from living organisms (oysters) and have been admired for centuries for their soft beauty and organic properties. Pearls take on the warmth of the wearer and feel almost alive when held. No other gem material has this quality. There are two basic classifications for pearls, natural and cultured. Natural means that the pearl was formed in the oyster without any assistance other than Nature’s. Cultured means that the oysters are carefully tended and a precise procedure is used to introduce a foreign substance which will result in the formation of a pearl by the oyster. In today’s pearl market, approximately 98-99% of the pearls produced for sale are cultured.

Pearls can be cultivated in freshwaters as well as salt water areas, wherever oysters can live. These pearl producing oysters are part of the animal kingdom called Mollusk. Within this category, there are other groups that can produce pearls, conchs and abalones, for example, but pearl producing oysters are overwhelmingly used today in the culturing process.

Since pearls come in a wide variety of colors and shapes based on the individual characteristics of the pearl producing oyster, personal preference is important in the selection process. Other factors such as blemishes and size do impact significantly on pearl value. Therefore, I would rate the four characteristics in the following order; purity (blemishes), size, color, and shape, from most important to least important.

Almost all pearls will have some natural blemishes; that is inherent in being natural. But if the blemishes distract from the luster of the pearl or its beauty, then it is considered a negative factor. Part of the purity of a pearl’s surface, besides the absence of blemishes, is the lustre of the pearl. This is due to the length of stay within the oyster of the pearl nucleus. There is a two to three year cultivation process needed to produce the necessary high lustre that indicates a high quality pearl. High lustre pearls appear almost mirror like and reflect light back to the eye like a mirror. Low lustre pearls have a soft look and the light reflection is diffuse. High lustre is better than low lustre, usually.

Size is ultimately determined by the size of the oyster. An oyster that measures only 3” across cannot produce a pearl much larger than 8.0mm. A larger oyster, such as found in the Tahitian Islands or the South Seas where the seas are warmer and the oysters grow larger, can produce a pearl well over 15.0mm. So size is relative to oyster type. It is important to note that it is very difficult for an oyster to produce a large pearl that is also nearly free of blemishes across its whole surface. That is one of the reasons that a matched strand of pearls can cost so much. Even matched pearls for earrings carry a premium because of this fact of life.

Add to the consideration of pearl value the colors produced by the various oysters. The inside lining of the oyster is critical to the color formation of the pearl. Therefore, there will always be a slight variation in pearls from one to the next due to the fact that the pearls come from different oysters. But within these perimeters, pearl colors can range from white to black in body color with the overtones or secondary colors ranging from pink, purple, green, yellow, bronze, blue, grey and black. Depending on a customer’s complexion, certain pearl colors will work well and others won’t. That is why this is more of a subjective issue.

The shape of the pearl is also subjective due to personal tastes. But since it is more difficult for the oyster to produce a round pearl, that is considered rarer than a baroque (or not round) pearl. Still some people love the organic quality of baroque pearls. Others like the simple perfection of round pearls. There is a shape for everyone. Although round pearls are more expensive due to the above factors, great bargains can be had for the person who wants quality and will accept a non traditional shape.